U.S. patent number 5,074,489 [Application Number 07/415,734] was granted by the patent office on 1991-12-24 for method and system for supporting an airborne vehicle in space.
Invention is credited to Eliyahu Gamzon.
United States Patent |
5,074,489 |
Gamzon |
December 24, 1991 |
Method and system for supporting an airborne vehicle in space
Abstract
A method and system for supporting an airborne vehicle in space
over a predetermined location and for an extensive period,
comprises coupling the airborne vehicle by cables to a plurality of
unmanned aircraft each having its own propulsion system;
controlling the unmanned aircraft to fly in circular orbits at
equally-spaced angles around the airborne vehicle while coupled to
the airborne vehicle, to tension the cables and thereby to support
the airborne vehicle in space over the predetermined location; and
supplying the unmanned aircraft with energy from an external source
to maintain the unmanned aircraft in flight over an extended or
indefinite period of time.
Inventors: |
Gamzon; Eliyahu (Rehovot,
IL) |
Family
ID: |
11059741 |
Appl.
No.: |
07/415,734 |
Filed: |
October 2, 1989 |
Foreign Application Priority Data
Current U.S.
Class: |
244/2; 244/26;
244/114R; 136/292; 244/59 |
Current CPC
Class: |
B64D
27/24 (20130101); B64D 1/22 (20130101); B64C
37/02 (20130101); Y02T 50/50 (20130101); Y10S
136/292 (20130101); B64D 2211/00 (20130101); Y02T
50/60 (20130101) |
Current International
Class: |
B64D
1/00 (20060101); B64D 27/24 (20060101); B64D
1/22 (20060101); B64D 27/00 (20060101); B64C
37/00 (20060101); B64C 37/02 (20060101); B64C
037/02 () |
Field of
Search: |
;244/2,26,158R,190,189,59,62,114R |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2754114 |
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Jul 1979 |
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DE |
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2951699 |
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Feb 1982 |
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DE |
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909198 |
|
Dec 1945 |
|
FR |
|
2141088 |
|
Dec 1984 |
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GB |
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Other References
1988 IEEE MTT International Microwave Symposium Digest vol. 1, 25
May 1988, New York pp. 283-286; J. J. Schlesack "A Microwave
Powered High Altitude Platform". .
NTIS Technotes: Dec. 1986; Springfield, Va., USA; p. 1299; K. D.
Castle; "Wireless Jump Starts for Partly Disabled
Equipment"..
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Primary Examiner: Peters, Jr.; Joseph F.
Assistant Examiner: Bidwell; Anne E.
Attorney, Agent or Firm: Barish; Benjamin J.
Claims
What is claimed is:
1. A method of supporting an airborne vehicle in space over a
predetermined location and for an extensive period, comprising:
coupling the airborne vehicle by cables to a plurality of unmanned
aircraft each having its own propulsion system;
controlling the unmanned aircraft to fly in circular orbits at
equally-spaced angles around the airborne vehicle while coupled to
the airborne vehicle, to tension the cables and thereby to support
the airborne vehicle in spaced over said predetermined
location;
supplying the airborne vehicle, while supported in space over said
predetermined location, with energy from an external source;
and
transferring energy from said airborne vehicle to said unmanned
aircraft to maintain the unmanned aircraft in flight over an
extended or indefinite period of time.
2. The method according to claim 1, wherein said unmanned aircraft
are electrically propelled and are supplied with electrical energy
from said external source.
3. The method according to claim 2, wherein said electrical energy
is supplied to the airborne vehicle from a microwave transmitter
located on the ground.
4. The method according to claim 2, wherein said electrical energy
is supplied to the airborne vehicle from solar cells located on the
airborne vehicle and transmitted to the unmanned aircraft via said
cables.
5. The method according to claim 2, wherein said electrical energy
is supplied to the airborne vehicle from a power plant located on
the ground and transmitting power to the airborne vehicle via a
further cable.
6. The method according to claim 2, wherein said electrical energy
is supplied to the airborne vehicle from a laser located on the
ground.
7. The method according to claim 1, wherein there are at least
three of said unmanned aircraft coupled to said airborne
vehicle.
8. The method according to claim 1, wherein the unmanned aircraft
support the airborne vehicle at an altitude of at least 50,000 feet
but less than 200,000 feet above sea level.
9. A launching facility for launching an airborne vehicle according
to claim 1, comprising a circular runway for the unmanned aircraft,
and a central bay for the airborne vehicle.
10. A system for supporting an airborne vehicle in space over a
predetermined location and for an extensive period, comprising:
a plurality of unmanned aircraft, each coupled by a cable to the
airborne vehicle;
control means for controlling the unmanned aircraft to fly a
circular orbit at equally-spaced angles around the airborne vehicle
while coupled thereto, to tension the cables and thereby to support
the airborne vehicle in space over said predetermined location;
energy-supplying means supplying said airborne vehicle, while
supported in space over said predetermined location, with energy
from an external source; and
means for transferring energy from said airborne vehicle to said
unmanned aircraft to maintain the unmanned aircraft in flight over
an extended or indefinite period of time.
11. The system according to claim 10, wherein said unmanned
aircraft include electrical propulsion devices and means for
supplying said devices with electrical energy from said external
source.
12. The system according to claim 11, wherein said means for
supplying electrical energy comprises a microwave transmitter
located on the ground.
13. The system according to claim 11, wherein said means for
supplying electrical energy comprises solar cells located on the
airborne vehicle for generating electrical energy transmitted to
the unmanned aircraft via said cables.
14. The system according to claim 11, wherein said means for
supplying electrical energy comprises a power plant located on the
ground and supplying power to the airborne vehicle via a further
cable.
15. The system according to claim 14, wherein said means for
supplying electrical energy comprises a laser located on the
ground.
16. The system according to claim 11, wherein there are at least
three of said unmanned aircraft coupled to said airborne
vehicle.
17. The system according to claim 11, further including a launching
facility for launching said unmanned aircraft, comprising a
circular runway for the unmanned aircraft, and a central bay for
the airborne vehicle.
Description
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates to a method and a system for
supporting an airborne vehicle in space. The invention is
particularly applicable for hovering an airborne vehicle at an
altitude of over 50,000 feet above sea level, and for extensive
periods of time such as one month or longer, but the invention
could also advantageously be used for supporting an airborne
vehicle at much lower altitudes and/or for shorter periods of
time.
There are many applications, both military and civilian, for
hovering an airborne vehicle, e.g., a payload-carrying platform, in
space over a predetermined location. High-altitude hovering (e.g.,
above 50,000 feet) is usually effected by geostationary satellites,
but such systems are extremely expensive to produce and to launch.
Low-altitude hovering may be effected by helicopters or balloons,
but the period of time for such hovering, as well as the altitude,
is very limited.
OBJECTS AND SUMMARY OF THE INVENTION
An object of the present invention is to provide a method and also
a system of supporting an airborne vehicle in space, having
advantages in the above respects.
The present invention provides a method of supporting an airborne
vehicle in space over a predetermined location and for an extensive
period, comprising: coupling the airborne vehicle by cables to a
plurality of unmanned aircraft each having its own propulsion
system; controlling the unmanned aircraft to fly in circular orbits
at equally-spaced angles around the airborne vehicle while coupled
to the airborne vehicle, to tension the cables and thereby to
support the airborne vehicle in space over said predetermined
location; supplying the airborne vehicle, while supported in space
over said predetermined location, with energy from an external
source; and transferring energy from said airborne vehicle to said
unmanned aircraft to maintain the unmanned aircraft in flight over
an extended or indefinite period of time.
In the described preferred embodiments, the unmanned aircraft are
electrically propelled and are supplied with electrical energy from
the external source. The electrical energy may be supplied from
various sources, including: a microwave transmitter located on the
ground, solar cells located on the airborne vehicle and transmitted
to the unmanned aircraft via the cables, a power plant located on
the ground and transmitting power to the airborne vehicle via a
further cable, or a laser located on the ground.
Preferably, there are at least three, e.g. three-five, unmanned
aircraft coupled to the airborne vehicle. The unmanned aircraft may
support the airborne vehicle at an altitude of at least 50,000,
preferably 60,000-100,000, feet above sea level.
The invention also provides a system for supporting an airborne
vehicle in space over a predetermined location. The invention also
provides a launching facility for launching the unmanned aircraft,
the launching facility comprising a circular runway for the
unmanned aircraft and a central bay for the airborne vehicle.
As will be more apparent from the description below, the method and
system of the present invention is capable of supporting an
airborne vehicle at any desired altitude in space, preferably
between 60,000 and 100,000 feet above sea level, but less than
200,000 feet for indefinite periods of time so long as energy is
supplied to the unmanned aircraft. Since the aircraft is unmanned,
they do not need bulky cockpits, life support equipment, large
propulsion systems, high-redundancy design, or other complicated
controls. Preferably, the airborne vehicle is suspended below the
orbit of the aircraft by means of cables coupling the aircraft to a
rotating anchor point on the airborne vehicle. The unmanned
aircraft should have very long wingspans of a laminar flow design
and a high aspect ratio.
The method and system of the present invention are to be
distinguished from aerial transporation techniques using a
plurality of aircraft, such as described in Alabrune U.S. Pat. No.
2,298,912 of Oct. 13, 1942, Alabrune U.S. Pat. No. 2,373,086 of
Apr. 10, 1945, and Wilson U.S. Pat. No. 4,416,436 of Nov. 22, 1983.
In such techniques, two manned aircraft are used for pickup,
transport and delivery of relatively heavy payloads. Since such
systems are used mainly for delivering payloads from one location
to another, they utilize manned aircraft flying at relatively low
altitudes. In contrast, the method and system of the prevent
invention are concerned with suspending a platform or other
airborne vehicle in a fixed location for an extended period of
time, and therefore use unmanned aircraft continuously supplied
from an external source of energy and preferably hovering at a very
high altitude, at least 50,000 feet above sea level.
Further features and advantages of the invention will be apparent
from the description below.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is herein described, by way of example only, with
reference to the accompanying drawings, wherein:
FIG. 1 illustrates one form of system constructed in accordance
with the present invention for supporting an airborne vehicle in
space over a predetermined location;
FIGS. 2 and 3 illustrate two other systems constructed in
accordance with the present invention; and
FIG. 4 illustrates a launching facility which may be used with any
of the systems of FIGS. 1-3.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 illustrates an airborne vehicle 2 supported in space over a
predetermined location by a plurality of unmanned aircraft 4 each
connected to the airborne vehicle 2 by a cable 6 fixed at one end
to the unmanned aircraft and at the opposite end to a rotating
anchor 8 secured to the airborne vehicle 2. The plurality of
unmanned aircraft 4 are externally controlled to fly in circular
orbits at equally spaced angles around the airborne vehicle 2, so
as to tension the cables 6 and thereby to support the airborne
vehicle 2 in space over any desired predetermined location.
The aircraft 4, being unmanned, may be of very simple construction
to exclude bulky cockpits, life support equipment, high redundancy
design subsystems, and the like. These aircraft have long wing
spans of laminar flow design and of a high aspect ratio. Their
cable 6 may be coupled to the body of the aircraft or to the tips
of their wings. Preferably three to five of such aircraft are used,
depending on the payload.
The unmanned aircraft 4 preferably support the airborne vehicle 2
in suspension at an altitude of at least 50,000 feet, e.g. between
60,000 and 100,000 feet above sea level. The airborne vehicle can
therefore serve many of the functions of a geostationary satellite
but hovers at a substantially lower altitude and therefore covers
substantially less ground area.
The unmanned aircraft 4 preferably include electrical propulsion
systems which may be continuously supplied from external energy.
FIG. 1 illustrates the externally-supplied energy being delivered
from solar panels 10 supported by the airborne vehicle 2. These
solar panels generate electricity which is supplied to the aircraft
4 via their cables 6, which serve as conduits for transmitting the
electrical power, as well as flexible couplings for supporting the
vehicle 2.
FIG. 2 illustrates a variation wherein the energy supplied to the
unmanned aircraft 4 is derived from a microwave transmitter 20
located on the ground and transmitting the energy to a rectenna 22
supported by the airborne vehicle 2. The rectenna, namely a
rectifying antenna, receives the transmitted microwave energy and
converts it directly to DC, which energy is then fed via the cables
6 to the unmanned aircraft. The stability and fixed alignment of
the rectenna requires neither a tracking ground antenna (moving and
rotating so as to remain focussed on and polarized with the
rectenna), nor a fixed spread beam with an unaligned polarity; this
arrangement therefore provides a relatively simple means for
transmitting the energy to the unmanned aircraft.
Microwave transmitter 20 may also be a high-power laser
transmitting a narrow beam of laser energy to, and rectenna 22 may
be a receiver for receiving the laser beam and for converting it to
electrical energy supplied to the unmanned aircraft 4 via their
cables 6.
FIG. 3 illustrates another arrangement which may be used, in which
the external electrical energy supplied to the unmanned aircraft 4
is derived from a power plant 30 located on the ground and
connected to the airborne vehicle 2 by means of another cable 32.
This technique is particularly useful when the airborne vehicle 2
is to hover at a relatively lower altitude, but calculations show
that lightweight materials, which are presently available for use
in constructing the cable 32, enable the power to be transmitted
from a ground station 30 to an altitude of 50,000 feet or
higher.
FIG. 4 illustrates a launching facility that may be used for
launching the unmanned aircraft 4 and the airborne vehicle 2. Such
a launching facility includes a circular runway 40 for the aircraft
4, and a central bay 42 for the airborne vehicle 2. All the
aircraft take-off in synchronization, and trace a helical path in
space as they ascend, the axis of the helical path being centered
on the bay 42 for the airborne vehicle 2. The aircraft continue
flying in this manner until the tension in all the cables 6 is
sufficient to raise the airborne vehicle 2, and once airborne, the
vehicle will climb and fly through the air in the same manner as a
helicopter's rotor disc.
The power required for initial take-off may be provided by an
auxiliary turbo-generator unit burning liquid fuel. When the
unmanned aircraft 4 and the suspended airborne vehicle 2 reach a
predetermined altitude, e.g., 40,000 feet, the turbo-generator unit
and its fuel cell may be released and parachuted back to the
ground. The vehicle then continues to fly and navigate until it
reaches the required position, and once there, it hovers
continuously correcting for all manners of drift.
Power for the operation of the airborne vehicle 2 and its payload,
the vehicle avionics, and the aircraft propulsion systems after the
release of the turbo-generator, is provided by an electrical power
generator integrated into the airborne vehicle and using the energy
supplied from the external sources, e.g., the solar panels 10 in
FIG. 1, the ground-located microwave or laser transmitter 20
illustrated in FIG. 2, or the ground-located power plant 30 coupled
to the airborne vehicle via a cable 32 as illustrated in FIG. 3.
Each unmanned aircraft may thus be of simple and light-weight
construction to include only its propulsion system and its wings.
The supporting of the airborne vehicle may be further aided by a
balloon secured to the airborne vehicle. The balloon may also
include solar cells for generating electricity and for transmitting
such generated electricity to the unmanned aircraft via the
cables.
While the invention has been described with respect to several
preferred embodiments, it will be appreciated that many other
variations, modifications and applications of the invention may be
made.
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